Here are just a few of the incredibly dangerous things that the Hogwarts administration thought was appropriate to have in a SCHOOL:
1. A giant squid that lived in the school lake
2. The entire concept of Hagrid's class, in which the students got to play with extremely dangerous animals
3. Detentions in the Haunted Forest, where the students got to interact with extremely dangerous animals
4. The freaking Chamber of Secrets
5. Quidditch (yes, we all love Quidditch, but that shit is dangerous)
6. Fluffy the dog. For real, what would they have done if Fluffy had eaten a kid?